Discover published sets by community

Date: 1977; Involved Space Agency: NA; Significance: Discovery of ecosystems based on chemosynthesis, showing life can thrive without sunlight, implications for life on other planets.

Date: October 4, 1957; Involved Space Agency: Soviet Union's Space Program; Significance: First artificial Earth satellite, marking the beginning of the space age.

Date: February 22, 2017; Involved Space Agencies: NA; Significance: Seven Earth-sized exoplanets discovered with potential for liquid water, increasing the probability of finding extraterrestrial life.

Date: August & September, 1977; Involved Space Agency: NASA; Significance: Longest operating spacecrafts, first human-made objects to enter interstellar space.

Date: August 6, 2012; Involved Space Agency: NASA; Significance: Most sophisticated rover to date, analyzing Martian climate and geology, assessing habitability.

Date: April 12, 1961; Involved Space Agency: Soviet Space Program; Significance: Yuri Gagarin became the first human to travel into space and orbit the Earth.

Date: July 20, 1976; Involved Space Agency: NASA; Significance: First successful landing on Mars, began the search for Martian life.

Date: April 24, 1990; Involved Space Agency: NASA with contribution from ESA; Significance: Allowed astronomers to observe the universe in unprecedented detail, advancing many fields of astrophysics.

Date: July 20, 1969; Involved Space Agency: NASA; Significance: First manned Moon landing, Neil Armstrong and Buzz Aldrin walked on the Moon.

Date: March 7, 2009; Involved Space Agency: NASA; Significance: Discovered thousands of exoplanets, expanding the knowledge of planetary systems.

Date: October 6, 1995; Involved Space Agencies: NA; Significance: First definitive detection of an exoplanet orbiting a sun-like star, highlighting the potential for other life-bearing systems.

Date: October 15, 1997; Involved Space Agencies: NASA, ESA, ASI; Significance: Provided extensive data on Saturn, its rings, and moons, including Titan's surface.

Date: November 26, 2018; Involved Space Agency: NASA; Significance: First mission dedicated to studying the deep interior of Mars, providing insights into the planet's seismic activity and internal structure.

Date: July 4, 1997; Involved Space Agency: NASA; Significance: Part of the Mars Pathfinder mission, it was the first rover to operate on Mars, paving the way for subsequent rovers.

Date: November 12, 2014; Involved Space Agency: ESA; Significance: First soft landing on a comet nucleus, provided insights on cometary composition and structure.

Date: Expected 2022; Involved Space Agency: NASA; Significance: Uncrewed test flight for NASA's Artemis program, intended to return humans to the Moon and prepare for crewed missions to Mars.

Date: February 18, 2021; Involved Space Agency: NASA; Significance: Carry a small helicopter named Ingenuity and seek signs of ancient life, collect samples for future return to Earth.

Date: April 10, 2019; Involved Space Agencies: EHT Collaboration; Significance: First direct visual evidence of a supermassive black hole and its shadow, confirming Einstein's general theory of relativity predictions.

Date: December 25, 2021; Involved Space Agencies: NASA, ESA, CSA; Significance: Next-generation space telescope designed to look further into the universe than ever before, potentially studying the atmosphere of exoplanets.